---
name: "CURLOPT_SSL_SESSIONID_CACHE"
section: "3"
platform: "macos"
package: "curl"
version: "166.0.0.0.1"
release: "macOS 26.5"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/CURLOPT_SSL_SESSIONID_CACHE"
---

# CURLOPT\_SSL\_SESSIONID\_CACHE(3)

use the SSL session-ID cache

## NAME

CURLOPT\_SSL\_SESSIONID\_CACHE - use the SSL session-ID cache

## SYNOPSIS

```
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_SESSIONID_CACHE,
                         long enabled);
```

## DESCRIPTION

Pass a long set to 0 to disable libcurl's use of SSL session-ID caching. Set this to 1 to enable it. By default all transfers are done using the cache enabled. While nothing ever should get hurt by attempting to reuse SSL session-IDs, there seem to be or have been broken SSL implementations in the wild that may require you to disable this in order for you to succeed.

## DEFAULT

1

## PROTOCOLS

All TLS-based

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    /* switch off session-id use! */
    curl_easy_setopt(curl, CURLOPT_SSL_SESSIONID_CACHE, 0L);
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
```

## AVAILABILITY

Added in 7.16.0

## RETURN VALUE

Returns CURLE\_OK if the option is supported, and CURLE\_UNKNOWN\_OPTION if not.

## SEE ALSO

[**CURLOPT\_DNS\_CACHE\_TIMEOUT**(3)](/CURLOPT_DNS_CACHE_TIMEOUT/3.md), [**CURLOPT\_MAXAGE\_CONN**(3)](/CURLOPT_MAXAGE_CONN/3.md), [**CURLOPT\_MAXLIFETIME\_CONN**(3)](/CURLOPT_MAXLIFETIME_CONN/3.md), [**CURLOPT\_SSLVERSION**(3)](/CURLOPT_SSLVERSION/3.md)